trying to print from MacBook via Canon Pixma ip1600

for Canon Printer

Unable to print. green & orange lights flash alternately. Screen says: "Error Number : 5100 A problem has occurred with the printer mechanism. Cancel printing and turn off the printer. Wait a few moments, then turn the power back on. If the problem persists, contact one of the service centers." Followed instructions, does not fix problem. Ink cartridges are probably dried up; have not used printer for some time; hesitate to just replace them without any indication that could make a difference.